Can ethernet be used for both direct connect and network access?

Cannot Connect to Internet via DSL or my LAN with a new computer

• I cannot get my newest computer to connect to my DSL modem and thus cannot use the LAN services of the modem nor access the internet. I have 5 computers connected to the DSL modem (visionnet adsl 202ER-4) Four of those computers (of various Windows operating systems) connect just fine. Two of the good ones are connected with ethernet cable and the other two good ones are connected via LinkSys Wireless-B access point (hence there is still room for the 5th computer - my new one.) On the new computer that fails, I have tried ethernet and wireless with the same failed results. For ethernet I tried the built-in LOM and also a PCI LAN card. One more thing yet that I have tried is to place a LinkSys Cable/DSL Firewall Router with 4-port switch between the new computer and the DSL modem (using ethernet wires.) I also connected a second Windows 2000 machine to this Router to prove that I set it up correctly. The other machine worked great and my new machine failed. I CAN connect to the Internet using a 56K modem just fine with the new computer. Also, I can use a secondary Network hub (or the Lynksys Router) and connect to another machine that way, in fact I can access the internet this way too if the other machine is set up to offer Internet Connection Sharing. But this workaround is not good enough for my needs. I returned the computer to the store where they connected it via a cable modem and it worked immediately for them without any configuration. I have verified that all ports on the modem are fine and the ethernet cables are good too. I have proven this by swapping the cables with good computers and swapping the ports they are plugged in to. I have also tried connecting only one computer to the DSL modem and removing the rest. The new computer (that cannot connect) is a Windows 2000 Pro Service Pack 4 and it is set up with similar settings as the two other Windows 2000 computers on my network. Two other computers are a Win98 and XP. The new computer has the following hardware: P4 2.6 Ghz Asus P4P800 Motherboard with 3Com Gigabit LOM (3C940) I have tried IPConfig /renew and pinging the 202ER-4 (which fails.) Interestingly, Windows shows that I am connected to the LAN, but no packets ever come back to it and I cannot see other computers on the network. I do not have a firewall nor anti-virus installed. TCP/IP is set up to obtain an IP address automatically, and also the DNS server address automatically. An acceptable answer doesn't have to be elaborate. It just needs to solve my problem of connecting to the Internet and LAN with my new computer. If you cannot solve the problem but can identify exactly where the problem lies then that would be worth half to me (but since this is the first time I've used Google Answers I don't know if there is a facility for awarding half answers.) Thanks.

• Answer:

  wschwader-ga: Thank you for the opportunity to help you overcome the connectivity problems with the new computer. Of course, since you ultimately found the cause of the problem yourself, it is a bit awkward to provide this Answer! It will help in documenting some of the useful techniques that can be used to debug connectivity problems in the future, though, so should be of value to you. The conflict between your LAN IP address space (10.0.0.x) and the IP address that your NetScreen client is set up for (10.0.0.x) was indeed the culprit here. The NetScreen client provides a VPN interface to Windows, allowing Windows to automatically establish and control a secure tunnel through the Internet to your company's Juniper Networks NetScreen VPN appliance. The problem here is that the address space conflict meant that, as soon as your 3COM Gigabit adapter received its IP address, the NetScreen Remote client would become active and take over the exact same address space. Therefore, requests (such as pings, etc.) intended for other machines in your local network, were instead being sent to the VPN interface. As those IP addresses do not exist in the company network at the other end of the tunnel, you would get no response whatsoever. A possible remedy, depending on how your company has configured the security policies for the NetScreen Remote client, is to change the address that the client listens on. You have inferred this already by suggesting that you change the address of either the client, or the local network. I am going to recommend that you leave the client alone for now, and change the local network instead. This means that you will not need to fiddle with the settings in Windows for VPN, with the potential to 'break' it. To change the local network, use a connected PC to access the web-based configuration interface of the Visionnet 202ER-4, at 10.0.0.2. After you have logged in, go to the LAN Configuration screen. Here, you will see several items that will need to be changed. The first is the DHCP address space from which the router assigns dynamic IP addresses to your network devices. Please change this from the factory defaults to the range of: 192.168.10.3 to 192.168.10.32 Yes, we are moving completely away from the 10.0.0.x subnet for your local network. Next, for the LAN IP address of the Visionnet 202ER-4, change it from 10.0.0.2 to 192.168.10.2, subnet mask 255.255.255.0. Leave the other settings as they were, and submit the changes. At this point, you will need to allow the router to restart, then you will need to use the "ipconfig /release" and "ipconfig /renew" commands to reacquire an IP address on your PCs (note that in W98, the command is "winipcfg", for W2K/XP it is "ipconfig"). Now, your new computer should be set up to access the local network resources through the 192.168.10.x subnet, and your NetScreen Remote client through the existing 10.0.0.x address. One potential problem here is that it is possible for your company's IT department to configure your VPN user profile such that the NetScreen Remote client would prevent 'Internet' traffic while active. So, if even after you change the local network's address space, you are only able to access the other PCs and the Internet with NetScreen disabled, that would be the reason. This capability exists as an optional security measure to prevent your PC from being a conduit between the Internet and the corporate network. -------------------------- One final note, regarding subnet masks. The mask is a binary mask, meaning that if you write out an IP address in binary, and the mask in binary, then anywhere that the mask has a 0, your PC will treat as being accessible through that IP address' gateway. Obviously, I cannot do this explanation justice using just words... and being a firm believer in not reinventing the wheel, I will instead suggest that you take advantage of this excellent resource available on (where else?) the World Wide Web: A Free Lecture-based Educational Course on IP Addressing and Subnetting http://www.learntosubnet.com/ Also, Learn to Subnet http://www.cramsession.com/articles/files/learn-to-subnet-part-i----9162003-1529.asp -------------------------- Please, do let me know if you run into further problems trying to get your local network's IP address range changed. As for the NetScreen Remote, you may want to enquire with your company IT department to see if they can tell you whether your user profile allows you to access your local network while the VPN tunnel is active. Regards, aht-ga Google Answers Researcher